Persons suffering from the reduction or loss of one or more sensory capabilities (e.g., the sense of sight, hearing, balance, or touch) typically suffer a restriction in the amount and/or quality of sensory information such persons may receive. Such reduction of sensory information may be caused by birth defects, bodily injury, and so on. In some examples, medical devices have been developed to allow a person to regain some level of lost sensory capability in some cases. For example, hearing aids, cochlear implants, and other devices designed to interact with the human ear have served to enhance the hearing capabilities of those suffering from some types or severities of hearing loss. However, such devices do not address all types of hearing loss issues.
To address such issues in other ways, systems have been developed to employ an unimpaired sense of a user to relay information that would ordinarily be received via another sense that is impaired for that particular user. For example, Braille is a tactile writing system that facilitates reading of written materials by the visually impaired. More recently, screen reader software has been developed that interprets information to be presented on a computer screen and presents that information via text-to-speech (TTS) or other audio or tactile output. Closed captioning has long been employed to provide speech and other audio information via text displayed on a television or motion picture screen. Descriptive Video Service® (DVS) is a video description service that provides additional audio information (e.g., speech) descriptive of the visual information being presented in a movie or television program.
Some electronic systems have been designed to provide visual information by way of a tactile input. Such systems are often called “tactile visual substitution systems” (TVSS). Some recent academic research has been focused on employing the human tongue as a conduit through which visual information may be communicated to the user. This type of TVSS is termed a “tongue display unit” (TDU), which may be employed as a type of tactile visual substitution device, includes an array of electrodes configured to apply electro-tactile stimulation in one or more patterns to areas of the dorsal (upper) side of a user's tongue to relay the visual information. The electrodes may be arranged on a medium to be placed in the mouth atop the tongue of the user. The electrodes are connected by multiple wires to a signal generator located outside the body and controlled via a microcontroller so that the signal generator produces stimulation pulses for application to the tongue via the electrodes. Using such systems, the average human tongue may be able to sense about a one order of magnitude difference in electro-tactile stimulation, from a low stimulation level that is just barely perceptible, to a high stimulation level at which the perceived stimulation starts becoming uncomfortably intense.
With the above concepts in mind, as well as others not explicitly discussed herein, various embodiments of systems and methods for tongue stimulation for communication of information to a user are disclosed herein.